Thread: small idol issue

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Ive still got a small idol issue with my 460 mustang. I switched the fuel back to 110 octane last year because the previous owner was running E85. And the carb was not set up with the proper metering blocks for E85, and it would not idol on its own. I can get it to idol now but only at 1800 to 2000 rpm. Its a 4150 double pumper, with a proform main body. Its jetted correctly the plugs look nice and tan colored all around.

I was considering upgrading to these proform metering blocks, has anyone had experienced the use of these?
http://www.jegs.com/i/Proform/778/67165C/10002/-1

Ive got a high lift cam, .670 in and out. A bit stout for street strip but thats what ive got to work with. does anyone think this is a good choice to try next, or have any other ideas? As always thanks in advance for any insight into this problem.

What metering blocks do you have now?

Any vacume leaks?

If it is idling that high you have the throttle plates open so far that the transfer slots and idle/transition system are not in the picture

Take the carb off, turn over and look at the throttle plates---they should be almost closed and you should just see a little of the transfer slot---if they aren't even , have burrs inside of them you will need to correct before going any further.

thanks for the reply jerry, It has no vacume leaks, ive sprayed it down with carb cleaner while running to check that. The blades are just barely barely open, I will check again to see how much of the transfer slot is showing, but each butterfly has a hole drilled into it, about 1/8" in size. Are they supposed to be drilled there?

The metering blocks on it now are the stock holley's. I was told when I got it that it was an 830 HP holley, but the main body has no mark, stamp, or number stating holley. So it probably can't be a holley. I am only assuming its a proform because I cant find another manufacturer that makes them.

I've seen and used the air holes in the throttle plates before and in some instances they do cure an Idle problem but in other they can make it worse.

You might try sealing them and see if that helps.

thanks mike, next weekend i will plug the holes and see what happens then. this whole week is shot on the nitro bike prep for next sunday.

Are you going to be at IRP NHRA regional race? We may be there with a BA/A trying to run 200 and in the 6s

I usually tap the center of the base plate 1/4 pipe thread and drill 100-125 hole in it for idle air and run solid butterflies. you have to mill a cross X it top side of the base plate so it can get some air from the throats
I find the carbs with the drilled throttle buterflies give too much air for street cars

I reread the postings here to see if I missed it. I haven't seen if you double checked your secondaries to be sure they are completely closed. Have you double checked those?